Hey guys, I am trying to figure out what the original part number for the 1969 Z/28 fan/alternator/smog belt is. I see in the AIM it says for a sbc with a manual it is GM3883248, but then see the repop guys list a part number GM3932457, although I didn't find this in the AIM. In addition to the part number I am also trying to figure out what is assembly line correct. I have seen 2 versions of GM belts, ones that have the GM number stamped/pressed in , and have also seen the part number raised off of the belt in a crisp font. See pic (Thank you Hans for digging those out)Hans pic of his belts came off a 69 Los Angeles car, not sure if the Norwood parts bin would be the same, or if there was an earlier and later version of the belt(s).

Hey guys, I am trying to figure out what the original part number for the 1969 Z/28 fan/alternator/smog belt is. I see in the AIM it says for a sbc with a manual it is GM3883248, but then see the repop guys list a part number GM3932457, although I didn't find this in the AIM. In addition to the part number I am also trying to figure out what is assembly line correct. I have seen 2 versions of GM belts, ones that have the GM number stamped/pressed in , and have also seen the part number raised off of the belt in a crisp font. See pic (Thank you Hans for digging those out)Hans pic of his belts came off a 69 Los Angeles car, not sure if the Norwood parts bin would be the same, or if there was an earlier and later version of the belt(s).

The 3883248 is listed under GM part belts as 47.5" in length vs. the GM3932457 listed at 46.5" in length. You probably know that Quanta sells the repro belts http://www.gastanks.com/prodinfo.asp?number=29-B-450 Later service replacement 3883248 belts had the same type of printing as the current quanta repro belt. Maybe back in the day GM had a couple suppliers and one had raised letters/numbers and the other supplier was opposite.

Hey Chick I recently saw that auction for that replacement belt as well, ( I also saved the pics), thanks for posting the pics. Hans and JKZ have had the raised original belts, which made me think the raised was assembly line correct. Is it any different for 67 or 68, did they use exclusively one style from the factory?

Hey Chick I recently saw that auction for that replacement belt as well, ( I also saved the pics), thanks for posting the pics. Hans and JKZ have had the raised original belts, which made me think the raised was assembly line correct. Is it any different for 67 or 68, did they use exclusively one style from the factory?

Wish I knew! I'm thinking 67 & 68 had a little different inch span so a different part number was needed. Since our 68Z restoration has the repro headers the smog is not used so never researched that topic properly. Not sure any of us would be surprised to know a couple suppliers were used which included both types of belt identification, but the only ones I remember were the ones similar to what Quanta sells. Need to check some of my NCRS judging books and see what they note back during that time frame.

Chick, I knew you guys would have some old relic of a judging book from back in the day. "What a great group of guys" that can go back in time and find resources like that...

The reference I was referring to is not old judging material but the latest in NCRS judging material as they continually update and add information with later edition manuals. Checking our 68/69 NCRS technical and judging manual on P81 it states "All GM belts have a GM part number molded as indentions into or as raised characters on the belt. White, green, or yellow GM numbers are a service replacement. Some original GM belts had the manufacturer logo stamped in color in the belt."So as we thought, they were both ways.

When judging do you compile any original pictures of certain parts to compare against future cars if there is questionability with a particular part or area of a particular car? I just thought you must see the best of the best, so a picture reference book of originality may be a tool possibly.